Boko Haram leader Abubakar Shekau released a video message on Tuesday claiming a series of attacks in northeast Nigeria during the festive season.

The shadowy leader released his first video message in months amid a surge in violence casting doubt on the Nigerian government’s claim that the jihadist group is defeated.

“We are in good health and nothing has happened to us,” said Shekau in the 31-minute video message spoken in the Hausa language common across northern Nigeria.

“Nigerian troops, police and those creating mischief against us can’t do anything against us, and you will gain nothing,” he said.

“We carried out the attacks in Maiduguri, in Gamboru, in Damboa. We carried out all these attacks.”

The video then shows footage from a Christmas Day attack on a military checkpoint in Molai village on the outskirts of the northeast Nigerian city of Maiduguri, which the military said was thwarted by troops after one hour of battle.

Boko Haram fighters in torn clothes were shown shooting from the back of battered pickup trucks.

Shekau’s message comes during an acceleration of Boko Haram attacks and just days after the jihadists killed 25 people outside Maiduguri, the birthplace of the Islamist insurgency.